Differential Diagnosis of Central-Side Wrist Pain
In previous posts, we have already talked about the most common wrist pathologies, injuries or disoders that cause radial pain, and how to diagnose them. Check it out before continuing here, as it will provide you with some important basics for Wrist or Carpal pain assessment.
👉Differential Diagnosis of Radial-Side Wrist Pain
In this post, we will analyse the diagnoses that can cause central wrist pain, both volar and dorsal, and how we can evaluate the causes of this pain.
It is important to remember that pain is a highly variable symptom among patients, so our Anamnesis and Clinical History should guide our Physical Examination of the Hand.
Diagnosis and Test for assessment of Central Wrist Pain
Scapholunate Ligament Injuries
The scapholunate ligament of the wrist (which, as the name suggests, is an intracarpal ligament between these two bones of the first row of the carpus) is a structure divided into three regions with different qualities:
1) The dorsal region: the most resistant and relevant in joint stability,
2) Proximal or Intermediate region: thinner and with oblique fibres, with a composition similar to fibrocartilage,
3) Palmar or volar region: less resistant portion of the ligament.
The affectation of this ligament is associated with falls with the hand outstretched, and is frequently associated with fractures of the distal radius (an estimated 54.5% of cases) (Ogawa 2013). On certain occasions when this ligament is affected, together with the secondary stabilisers and the neuromuscular control system itself, it can cause a situation of carpal instability.
👉What is carpal instability? When can I say that a carpus is unstable?
The patient with scapholunate ligament injury will present with symptoms such as diffuse pain, oedema, progressive loss of strength, a feeling of instability (“as if losing control of their hand”), noises and joint jumpings. The patient often attends to consultant after months of the injury.
1) Tenderness on palpation of the scapholunate joint: the joint is easily located at the dorsal aspect of the wrist, and with slight wrist flexion. It is palpated 1 cm distal to the lister tubercle of the radius.
2) Scaphoid Shift Test (or Watson Test): this test looks for the presence of instability at the level of the scapholunate joint. To do this, the patient rests the elbow on a table, and the therapist places his thumb on the distal and volar pole of the scaphoid, leaving the rest of the fingers on the dorsal wrist.
Once in this position, the therapist starts the test in Ulnar Deviation and Slight Extension, and progressively moves to Radial Deviation and Slight Flexion. The lack of space at the radial fossa physiologically causes the scaphoid goes into flexion, which is perceived as a “push” of the scaphoid on the examiner’s thumb.
The movement is then repeated but applying pressure on the distal pole of the scaphoid with the thumb, preventing the scaphoid from falling into flexion. In case of complete injury to the scapholunate ligament, the scaphoid will subluxate dorsally, outside the scaphoid fossa of the radius. This is because the ligament is non-functional, and does not transmit forces between the lunate and scaphoid. When the pressure of the thumb on the scaphoid is relieved, the scaphoid returns to its physiological position with a characteristic sound as it falls on the dorsal edge of the radius.
This test includes more subtle findings such as “laxity” and pain, so it should always be done bilaterally. Moreover, it is claimed that 36% of normal wrists may have some degree of laxity and give positive results.
3) Scaphoid Ballotement Test: this test aims to evaluate the laxity between the scaphoid and lunate. To do this, with the forearm pronated, the examiner stabilises the lunate between his fingers, and with the other hand, performs translations in the volar-dorsal direction of the scaphoid. This should always be compared with the contralateral side.
👉Do you understand the Biomechanics of the carpus? Do you want to go deeper into the scapholunate ligament injury? We have a full entry talking about Biomechanics, Injury and Instability!
SLAC Wrist
The SLAC (Scapholunate Advanced Collapse) wrist is an advanced situation of scapholunate instability, in which this disorder is maintained over time. The alteration of the biomechanics of the carpus and the existing dissociation between the scaphoid bone and the lunate produces deformations of the carpus and characteristic arthritic changes.
Stage 1: Arthritic changes at the Radial Styloid
Stage 2: Arthritic changes at the Radial-Scaphoid Fossa
Stage 3: Arthritic changes at the midcarpal level
The picture below shows on the left, a SLAC wrist stage 2 (note the arthritic changes at the radioscaphoid level) and on the right, a SLAC wrist stage 3 (changes in the radioscaphoid fossa and capitolunate joint):
Kienböck Disease
Kienböck’s disease is an avascular necrosis of the lunate bone that may present with central pain at the wrist. Its aetiology is unknown, although a multifactorial origin is suggested: anatomical, biomechanical, vascular and/or traumatic.
It usually affects men aged between 20-40 years who perform demanding work with their hands on a recurrent basis. These patients will report diffuse pain, associated with gestures such as gripping or when loads are applied, and limited mobility.
Below you can see an X-ray of a wrist with Kienböck’s disease stage II, characterised by necrosis of the lunate (clearly seen in the image) but WITHOUT bone collapse.
👉We have a complete post talking about Kienböck’s Disease: Etiology, Diagnosis, Litchman’s Stages, Conservative and Surgical Treatment and CASE REPORT.
Palmar Midcarpal Instability
Palmar midcarpal instability is a type of non-dissociative carpal instability (CIND), as it is not related to dissociation between bones of the same carpal row, but affects the midcarpal joint. This alteration of the relationship between the two rows causes an alteration of the synchrony of the carpal bones, which will lead to biomechanical problems.
Its presence is associated with pain, weakness, a feeling of instability, oedema, joint popping and noises.
1) “Catch-Up Clunk” sign: characteristic sign appearing at ulnar wrist deviation, which may be self-induced by the patient or by the practitioner, and is often audible and/or visible.
Because the relationship between the carpal bones between the two rows is altered, the carpal bones of the proximal row do not perform their physiological movement. Consequently, when the wrist is brought from radial to ulnar deviation, these bones would not accompany the gesture until the end of the movement, producing an abrupt jump or correction in flexion of the entire proximal row.
2) Lichtman Midcarpal Shift Test: this test seeks to evaluate the displacement of the midcarpus to detect the presence of instability. To do this, the examiner stabilises the patient’s forearm in pronation with one hand, and with the opposite hand, places his/her thumb on the Capitate, to apply a force in the volar direction of the distal row of the carpus. Maintaining this position, the examiner brings the wrist into ulnar deviation.
The test is positive when a sound (painful or not) is produced when the movement is performed (similar explanation to the previous test, due to the release of the carpal bone blockage).
👉 Entry with ALL the information you need to Understand Palmar Midcarpal Instability | Biomechanics, Types, Diagnosis, Classification, Exercise, Sensorimotor System and Surgery.
Dorsal and Volar Wrist Ganglions
The Ganglions are mostly benign tumours, which may disappear spontaneously and are usually asymptomatic. Even in those that are painful, mobility and function are usually preserved. Few require a surgical approach.
In the dorsal ganglions (the most frequent, 70%), it has been observed that they are related to the dorsal scapholunate region: dorsal scapholunate ligament, dorsal intercarpal ligament or DIC, and the dorsal scapholunate septum (DCSS). It is hypothesised to be caused by mucoid dysplasia associated with intracapsular and extradinovial ganglions of the dorsal scapholunate region. This dysplasia eventually herniates and affects the midcarpal joint.
Volar ganglions are less frequent (20%), and usually occur at the radiocarpal (rarely at the midcarpal level) and in scapho-trapezio-trapezoid arthritis. They are due to the destruction of the capsule at the volar insertion of the scapho-semilunar ligament at the midcarpal level.
👉 Learn how to diagnose Scapho-Trapezio-Trapezoid Arthritis.
ReHand in Central Wrist Pain Diagnoses
ReHand is a technology that combines the latest evidence in the sensorimotor system approach with artificial intelligence, and is applied to injuries such as those presented in this post. ReHand is a tool that allows you to prescribe, treat and monitor your patients objectively. In addition, it increases adherence to treatment, and improves health outcomes by speeding up recovery times.
💢Get to know it and ask for your demo!💢
References
Reavey PL, Hammert WC. Examination of the Wrist. Plast Reconstr Surg. 2021;284E-294E.
Newton AW, Hawkes DH, Bhalaik V. Clinical examination of the wrist. Orthop Trauma [Internet]. 2017;31(4):237–47. Available from: http://dx.doi.org/10.1016/j.mporth.2017.05.009
Mathoulin C, Gras M. Arthroscopic Management of Dorsal and Volar Wrist Ganglion. Hand Clin [Internet]. 2017;33(4):769–77. Available from: https://doi.org/10.1016/j.hcl.2017.07.012
Kuliński S, Gutkowska O, Mizia S, Martynkiewicz J, Gosk J. Dorsal and volar wrist ganglions: The results of surgical treatment. Adv Clin Exp Med. 2019;28(1):95–102.
Chim H, Moran SL. Wrist essentials: The diagnosis and management of scapholunate ligament injuries. Plast Reconstr Surg. 2014;134(2):312–22.
Cross D, Matullo KS. Kienböck disease. Orthop Clin North Am. 2014;45(1):141–52.
Wolff AL, Wolfe SW. Rehabilitation for scapholunate injury: Application of scientific and clinical evidence to practice. J Hand Ther. 2016;29(2):146–53.
Pablo Rodríguez Sánchez-Laulhé
Physiotherapist, PhD Candidate and Health Researcher | Hand Therapy and Digital Health
